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AM-1155 is a newly synthesized 6-fluoro-8-methoxy quinolone. We assessed its in vitro antimycobacterial activity using sparfloxacin (SPFX) and ofloxacin (OFLX) as comparison drugs. The MICs of these agents for various mycobacterial strains were determined by the agar dilution method with 7H11 medium. AM-1155 had lower MICs for 50 and 90% of tested strains of Mycobacterium kansasii, M. marinum, and M. fortuitum-M. chelonae complex than SPFX and OFLX, and the values for M. tuberculosis, M. scrofulaceum, and the M. avium-M. intracellulare complex were similar to those of SPFX and considerably lower than those of OFLX. In addition, the antimicrobial activity of AM-1155 against M. tuberculosis and M. intracellulare phagocytosed into murine peritoneal macrophages was compared with that of OFLX. AM-1155 (1 microgram/ml) inhibited the intracellular growth of both M. tuberculosis and M. intracellulare, whereas OFLX at the same concentration failed to show any such effect. Moreover, AM-1155 (10 micrograms/ml) exhibited a steady bactericidal action against M. tuberculosis, whereas OFLX at the same concentration had only a weak effect. AM-1155 (10 micrograms/ml) also inhibited the growth of M. intracellulare more effectively than OFLX.  相似文献   

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We determined the inhibitory activities of gatifloxacin against Staphylococcus aureus topoisomerase IV, Escherichia coli DNA gyrase, and HeLa cell topoisomerase II and compared them with those of several quinolones. The inhibitory activities of quinolones against these type II topoisomerases significantly correlated with their antibacterial activities or cytotoxicities (correlation coefficient [r] = 0.926 for S. aureus, r = 0.972 for E. coli, and r = 0.648 for HeLa cells). Gatifloxacin possessed potent inhibitory activities against bacterial type II topoisomerases (50% inhibitory concentration [IC50] = 13.8 microg/ml for S. aureus topoisomerase IV; IC50 = 0.109 microg/ml for E. coli DNA gyrase) but the lowest activity against HeLa cell topoisomerase II (IC50 = 265 microg/ml) among the quinolones tested. There was also a significant correlation between the inhibitory activities of quinolones against S. aureus topoisomerase IV and those against E. coli DNA gyrase (r = 0.969). However, the inhibitory activity against HeLa cell topoisomerase II did not correlate with that against either bacterial enzyme. The IC50 of gatifloxacin for HeLa cell topoisomerase II was 19 and was more than 2,400 times higher than that for S. aureus topoisomerase IV and that for E. coli DNA gyrase. These ratios were higher than those for other quinolones, indicating that gatifloxacin possesses a higher selectivity for bacterial type II topoisomerases.  相似文献   

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Alternate mutations in the grlA and gyrA genes were observed through the first- to fourth-step mutants which were obtained from four Staphylococcus aureus strains by sequential selection with several fluoroquinolones. The increases in the MICs of gatifloxacin accompanying those mutational steps suggest that primary targets of gatifloxacin in the wild type and the first-, second-, and third-step mutants are wild-type topoisomerase IV (topo IV), wild-type DNA gyrase, singly mutated topo IV, and singly mutated DNA gyrase, respectively. Gatifloxacin had activity equal to that of tosufloxacin and activity more potent than those of norfloxacin, ofloxacin, ciprofloxacin, and sparfloxacin against the second-step mutants (grlA gyrA; gatifloxacin MIC range, 1.56 to 3.13 microg/ml) and had the most potent activity against the third-step mutants (grlA gyrA grlA; gatifloxacin MIC range, 1.56 to 6.25 microg/ml), suggesting that gatifloxacin possesses the most potent inhibitory activity against singly mutated topo IV and singly mutated DNA gyrase among the quinolones tested. Moreover, gatifloxacin selected resistant mutants from wild-type and the second-step mutants at a low frequency. Gatifloxacin possessed potent activity (MIC, 0.39 microg/ml) against the NorA-overproducing strain S. aureus NY12, the norA transformant, which was slightly lower than that against the parent strain SA113. The increases in the MICs of the quinolones tested against NY12 were negatively correlated with the hydrophobicity of the quinolones (correlation coefficient, -0.93; P < 0.01). Therefore, this slight decrease in the activity of gatifloxacin is attributable to its high hydrophobicity. Those properties of gatifloxacin likely explain its good activity against quinolone-resistant clinical isolates of S. aureus harboring the grlA, gyrA, and/or norA mutations.  相似文献   

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OBJECTIVES: Until relatively recently southern Europe was regarded as having a medium to low multiple sclerosis prevalence, of about 20 or less per 100,000. However, recent studies in Sardinia, Sicily, continental Italy, Cyprus and Spain have yielded higher MS prevalence rates, between 32 and 102.6 per 100,000. We present the results of a prevalence study of MS in the municipality of M6stoles, central Spain. MATERIAL AND METHODS: To ascertain the prevalence of multiple sclerosis in M6stoles (195,979 inhabitants), an intensive study was undertaken using several sources of information. We used the Poser criteria in diagnosis. RESULTS: There were 85 patients (53 women and 32 men) classified as definite or probable, prevalence 43.4/100,000 (95% CI, 34.7 to 53.7). The incidence rate was 3.8/100,000/year (95% CI, 2.7 to 5.3) in the last 5 years. Mean age on prevalence day was 38.8+/-10.9 years. Mean age at onset was 31.7+/-9.3 years. Mean interval between initial symptoms and diagnosis was 1.7 years. Mean duration of disease was 7.6+/-6.1 years. Overall, 70.6% had a relapsing-remitting course, 18.8% had a primary progressive and 10.5% had a secondary progressive. Mean EDSS score was 2.7+/-1.9. CONCLUSION: The M6stoles study confirms the conclusions of previous smaller population studies that Spain is a moderately high or medium MS risk zone.  相似文献   

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The activity of cefamandole was comparable to that of cephalothin, cefazolin, and cephaloridine against Staphylococcus aureus, Streptococcus pyogenes, and Diplococcus pneumoniae. In contrast, cefamandole was considerably more active than cephalothin, cefazolin, or cephaloridine against gram-negative facultative bacilli, including Haemophilus influenzae, the most striking disparities being noted with indole-positive Proteus and Enterobacter. Bacteroides fragilis was more susceptible to cefoxitin than to cefamandole or cefazolin (median minimal inhibitory concentration, approximately 8, 32, and 32 mug/ml, respectively); cephalothin exhibited still less activity against this species. The majority of other anaerobes were inhibited by relatively low concentrations of all four cephalosporins. The results indicate a potentially valuable role for cefamandole against facultative gram-negative bacilli, including H. influenzae, but no exceptional activity against anaerobes.  相似文献   

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BACKGROUND: The purpose of this study was to describe infertile patients' experiences and assessment of infertility treatment. METHODS: Sixteen couples undergoing infertility treatment at the Fertility Clinic, Herlev Hospital in Copenhagen County. Denmark, were interviewed using a semi-structured qualitative interview. The participants were selected by purposeful sampling with maximum variation. The interviews were audiotaped and transcribed in full. Data were analyzed by the Grounded theory method. RESULTS: Infertility patients preferred treatment that was organized in a separate clinic where there were only a few staff-members, proceeded without waiting time, and followed a plan known to both the doctor and the couple. Satisfaction or dissatisfaction with treatment was not related to length of infertility, sex, or social class. Surprisingly, assessment of treatment was not related to either outcome or type of treatment. The participants experienced infertility treatment as a psychological strain and they felt that their emotional needs were not met in the health care system. The desire for services from the health care system was related to how the participants managed their infertility problem in relation to other people. The more open-minded the participant was, the more was expected from the professionals. These participants wanted detailed information about technical aspects of infertility and treatment as well as psychosocial and sexual advice and support. CONCLUSION: The public health care system does not meet the needs of infertile couples for information, psychological and sexual counselling, and discussions of alternative ways of becoming parents. High-quality treatment has to consider the patients' different needs and ensure successful pregnancies as well.  相似文献   

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The in vitro activity of levofloxacin was compared to the activities of ofloxacin, ciprofloxacin, ampicillin-sulbactam (2:1), cefoxitin, and metronidazole for a selected group of anaerobes (n = 175) isolated from skin and soft tissue infections by using the National Committee for Clinical Laboratory Standards-approved Wadsworth method. Ampicillin-sulbactam and cefoxitin inhibited 99% of the strains of this select group, levofloxacin and ofloxacin inhibited 73 and 50%, respectively, at 2 microg/ml, and ciprofloxacin inhibited 51% at 1 microg/ml. The geometric mean MIC of levofloxacin was lower than those of ofloxacin and ciprofloxacin for every group except Veillonella.  相似文献   

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In five experiments, in which subjects were to identify a target word as it was gradually clarified, we manipulated the target's frequency of occurrence in the language and its neighborhood size--the number of words that can be constructed from a target word by changing one letter, while preserving letter position. In Experiments 1-4, visual identification performance to screen-fragmented words was measured. In Experiments 1 and 2, we used the ascending method of limits, whereas Experiments 3 and 4 presented a fixed-level fragment. In Experiment 1, there was no relation between overall accuracy and neighborhood size for words between three and six letters in length. However, more errors of commission (guesses) were made for high-neighborhood words and more errors of omission (blanks) were made for low-neighborhood words. Letter errors within guesses occurred at serial positions having many neighbors, and these positions were also likely to contain consonants rather than vowels. In Experiment 2, a small facilitatory effect of neighborhood size on both high- and low-frequency words was found. In contrast, in Experiments 3 and 4, using the same set of words, inhibitory effects of neighborhood size, but only for low-frequency words, were found. Experiment 5, using a speeded identification task, showed results parallel to those of Experiments 3 and 4. We suggest that whether neighborhood effects are facilitatory or inhibitory depends on whether feedback allows subjects to disconfirm initial hypotheses that the target is a high-frequency neighbor.  相似文献   

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Four hundred thirty-eight bacteria cultured from specimens of patients with serious intra-abdominal infections were tested by agar dilution against trovafloxacin and other quinolones and antimicrobial agents. Trovafloxacin inhibited 435 strains (99.3%) at < or =2 microg/ml. All the quinolones had similar activities against Enterobacteriaceae and Pseudomonas sp., but trovafloxacin showed superior activities against streptococci, enterococci, and anaerobic organisms. Because of its excellent in vitro activities against diverse bacteria, trovafloxacin has potential use as a single agent for polymicrobial infections.  相似文献   

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The in vitro activities of eight quinolones against 115 coryneform bacteria (20 Corynebacterium jeikeium, 15 Corynebacterium minutissimum, 15 Corynebacterium striatum, 25 Corynebacterium urealyticum, 10 Corynebacterium xerosis, 10 Corynebacterium group ANF-1, 10 Corynebacterium group 12, and 10 Listeria monocytogenes) were determined. The MICs of ciprofloxacin, ofloxacin, and sparfloxacin for 90% of C. jeikeium, C. urealyticum, and C. xerosis isolates tested were > 16 micrograms/ml. Those of BAY Y 3118 and clinafloxacin against these species were 0.5 and 1 to 2 micrograms/ml, respectively. The MICs for 90% of all 115 strains tested were 0.5 microgram/ml for BAY Y 3118, 1 microgram/ml for clinafloxacin, 2 micrograms/ml for E-5068, 4 micrograms/ml for E-5065, and > 16 micrograms/ml for ciprofloxacin, ofloxacin, sparfloxacin, and E-4868.  相似文献   

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In-vitro/in-vivo correlations (IVIVC) are useful for predicting in-vivo results from in-vitro data. An IVIVC has been used to optimize a hydrocolloidal-based matrix tablet designed to be bioequivalent to an existing once-daily diltiazem HC1 product (Dilacor XR 240mg; Rhone-Poulenc Rorer). Data from a preliminary formulation dosed to fasted and fed subjects were used to establish the IVIVC. The correlation was then used during reformulation of the dosage forms to predict changes in the maximum plasma concentration (Cmax) and the area under the plasma-concentration-time curve (AUC) for fasted and fed subjects using in-vitro dissolution data. The IVIVC adequately predicted plasma profiles of two optimized formulations in studies with fasted and fed subjects.  相似文献   

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Azithromycin exhibited in-vitro activity against 20 clinical isolates of Mycobacterium avium complex for which the MIC90 was 32 mg/L and 22 clinical isolates of other mycobacteria but showed no activity against 20 isolates of Mycobacterium tuberculosis (MIC90 > 128 mg/L) nor against the single isolate of Mycobacterium marinum tested (MIC 128 mg/L). These results suggest that the drug may prove useful for the prophylaxis and treatment of infections due to non-tuberculous mycobacteria, including M. avium complex in patients with AIDS.  相似文献   

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A total of 435 clinical isolates of anaerobes were tested with a broth microdilution method to determine the activity of BAY y 3118 compared with those of other agents against anaerobic bacteria. All strains of Bacteroides capillosus, Prevotella spp., Porphyromonas spp., Fusobacterium spp., Clostridium spp., Eubacterium spp., Peptostreptococcus spp., and Veillonella parvula were susceptible (MICs of < or = 2 micrograms/ml) to BAY y 3118. Against the 315 strains of the Bacteroides fragilis group, five strains required elevated MICs (> or = 4 micrograms/ml) of BAY y 3118. Only imipenem and metronidazole were active against all anaerobes. Overall, BAY y 3118 was more active than ciprofloxacin, sparfloxacin, piperacillin, cefotaxime, and clindamycin against the test isolates.  相似文献   

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Dispersal of non-sporeforming anaerobic bacteria was studied. Skin samples were taken from the subjects, and dispersed from different parts of the body was examined. The number of anaerobic bacteria dispersed was not correlated to their density on the surface of skin area exposed. The highest density of anaerobic bacteria on the skin was found in the face and upper trunk, but the highest yield of anaerobic bacteria dispersed came from the lower trunk. The dominant anaerobic bacteria dispersed were Propionibacterium acnes, but Propionibacterium avidum, Propionibacterium granulosum and Gram-positive cocci were also isolated from the dispersal samples. Peptococcus magnus was the most common coccus isolated. For the less frequently isolated bacteria, the best correlation was found between the perineal flora and airborne bacteria. A comparison was also made of bacterial dispersal by naked and dressed subjects. The dispersal of both aerobic and anaerobic bacteria was higher when the subjects were dressed in conventional operating theatre cotton clothing than when they were naked. The increased dispersal of anaerobic bacteria when the subjects were dressed was mainly due to increased dispersal of Propionibacterium sp.  相似文献   

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The antimicrobial susceptibility of 492 anaerobic bacteria, the majority of which were recent clinical isolates, was determined by the agar dilution technique. Penicillin G was active against most of the strains tested at 32 U or less/ml, but only 72% of Bacteroides fragilis strains were susceptible at this level and 9% required 256 U or more/ml. Ampicillin was effective against most of the strains except B. fragilis at 16 mug or less/ml. Amoxicillin was active against only 31% of B. fragilis, 76% of other Bacteroides species, and 67% of Fusobacterium species at 8 mug/ml. Two new penicillins, mezlocillin and azlocillin, were similar to ampicillin in their activity. Carbenicillin and ticarcillin inhibited all but a few strains at 128 mug or less/ml. BLP 1654 was somewhat more active than penicillin G against B. fragilis but had similar activity against other anaerobes. Cephalothin was inactive against B. fragilis, and only 65% of other Bacteroides species were inhibited by 32 mug or less/ml. It was effective against all other anaerobes at that level. Cefamandole showed somewhat greater activity than cephalothin against B. fragilis but generally less activity against gram-positive organisms. Cefazaflur (SKF 59962) was comparable to cephalothin against B. fragilis. Cefoxitin was distinctly more active than cephalothin against B. fragilis. These latter two agents were less active than cephalothin against the gram-positive anaerobes. Chloramphenicol remains active against anaerobic bacteria at 16 mug or less/ml, with rare exceptions. Thiamphenicol was similar to chloramphenicol in its activity. Clindamycin was very active against most of the anaerobes at 8 mug or less/ml. Erythromycin and josamycin were also tested, with josamycin showing greater activity against B. fragilis than either erythromycin or clindamycin. A new oligosaccharide, everninomicin B, was less active than clindamycin against B. fragilis but more active against clostridia and some of the other strains tested. Most of the groups of bacteria tested demonstrated a trend toward resistance to tetracycline. Doxycycline and minocycline were somewhat more active than was tetracycline. Metronidazole was active against the majority of the anaerobes tested; resistance ws demonstrated by some of the gram-positive cocci and gram-positive, non-sporeforming bacilli.  相似文献   

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Propagermanium (3-oxygermylpropionic acid polymer) is an organic germanium compound that activates the immune system. In this study, we investigated the action of propagermanium on T-cell-mediated murine hepatic injury induced by concanavalin A (Con A). Oral administration of propagermanium inhibited the development of liver injury about 10 h after ConA injection. Histological analysis demonstrated that propagermanium attenuated the extent of liver damage compared with controls, reducing infiltration by leucocytes, especially CD11b-positive cells. Infiltration by CD4-positive cells was not affected. Tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma are crucial for the development of hepatitis in this model. Propagermanium treatment induced significant inhibition of subsequent TNF-alpha production about 10 h after Con A injection, without affecting IFN-gamma, interleukin (IL)-10, IL-4 and IL-12 production. This effect on TNF-production coincided with the inhibition of aminotransferase activity late in the progression of Con A-induced liver injury. These facts suggest that this compound affects the macrophages (Mphi) function in the liver sinusoid. Therefore, Mphi were cultured with liver sinusoidal endothelial cells (SEC) and the effect of propagermanium on TNF-alpha production in the presence of IFN-gamma was determined. TNF-alpha production was reduced significantly in the coculture of Mphi and SEC when Mphi was treated with propagermanium. These results might explain the mechanisms by which propagermanium inhibits Con-A-induced liver injury. That is, propagermanium improves hepatitis through mechanisms including the reduced production of TNF-alpha, without modification of Th1- and Th2-cell function.  相似文献   

20.
E-4695, (-)-7-[3-(R)-amino-2-(S)-methyl-1-azetidinyl]-1-cyclopropyl-1,4- dihydro-6-fluoro-4-oxo-1,8-naphthyridine-3-carboxylic acid, is a new fluorinated naphthyridine with an azetidine moiety. The MICs of E-4695 at which 90% of the isolates were inhibited (MIC90s) were 0.06 to 0.5 microgram/ml for gram-positive cocci, including species of the genera Staphylococcus, Streptococcus, and Enterococcus, and the MIC90s against gram-negative pathogens such as members of the family Enterobacteriaceae (with the exception of Providencia spp. [MIC90, 8 micrograms/ml]) and Pseudomonas aeruginosa were 0.015 to 0.5 microgram/ml. E-4695 inhibited 90% of the Clostridium perfringens and Bacteroides fragilis isolates at 0.25 and 4 micrograms/ml, respectively. Against gram-positive cocci the potency of E-4695 was 2- to 8-fold higher than that of ciprofloxacin, 4- to 8-fold higher than that of ofloxacin, and 8- to 16-fold higher than that of fleroxacin. Against enteric bacteria and P. aeruginosa the potency of E-4695 was, in general, similar to that of ciprofloxacin and eightfold higher than those of ofloxacin and fleroxacin. E-4695 was four- and eightfold more potent than ciprofloxacin against C. perfringens and B. fragilis isolates, respectively. E-4695 and ciprofloxacin showed similar properties when the effects of pH or magnesium concentration were tested on them. E-4695 and ciprofloxacin had substantial reductions of activity only when pH decreased below 4.8. E-4695 and ciprofloxacin activities were not markedly affected by the presence of 5 or 10 mM Mg2+. The presence of serum and human urine at pH 7.2 decreased the activity of E-4695 between two- and fourfold. After an oral dose of 50 mg/kg of body weight, the maximum level in serum, the biological half-life, and the area under the concentration-time curve from 0 to 10 h for E-4695 were 13.2 microgram/ml, 3.3 h, and 45.6 microgram . h/ml, respectively. The area under the concentration-time curve from 0 to 4 h for ciprofloxacin was 2.3 microgram . h/ml at the same dose. Fifty-percent effective doses (ED50S) against Staphylococcus aureus HS-93 infections in mice were 4.5 mg/kg with E-4695 and 37.6 mg/kg with ciprofloxacin. Infection with Streptococcus pneumoniae 29206 was more effectively treated with E-4695 (ED50, 41,2 mg/kg) than with ciprofloxacin (ED50, 200 mg/kg). The ED50 of E-4695 for infections with Streptococcus pneumoniae 1625 was 132.2 mg/kg; ciprofloxacin was ineffective at 400 mg/kg against this strain. E-4695 was also more potent than ciprofloxacin in treatment of infections caused by gram-negative organisms such as Escherichia coli HM-42 (ED50S, 1.0 and 3.9 mg/kg, respectively). The ED50S of E-4695 and ciprofloxacin were 33.0 and 145.5 mg/kg against P. aeruginosa HS-116 and 9.6 and 18.9 mg/kg against P. aeruginosa B-120, respectively. The therapeutic efficacy of E-4695 may depend not only on its in vitro activity but also on its improved pharmacokinetic properties.  相似文献   

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